Peripheral Artery Disease Negatively Impacts Gait Function in Patients with Below-Knee Amputation with Targeted...

Peripheral artery disease (PAD) is frequently associated with peripheral neuropathy and is often compounded by comorbidities such as diabetes. PAD significantly increases the risk of lower extremity amputation, particularly below-knee amputation (BKA), which may severely impair patients' mobility. Although recent surgical advances, such as targeted muscle reinnervation (TMR), have improved outcomes in pain and neuroma formation, patients with PAD who undergo BKA with TMR may still face some functional challenges. Therefore, this study aimed to investigate the impact of PAD in patients undergoing BKA with TMR on their lower extremity function.

A single-center study was conducted from June 2021 to July 2024. Adult patients who could safely ambulate without open wounds or lower extremity surgery within 90 days were included. PAD status and BKA with TMR history were documented through a retrospective chart review. Participants completed 120-sec walk and 30-sec Romberg sway tests with wearable sensors. Gait data were collected through Motility Lab software, speed (m/s), elevation midswing (cm), step duration (s), cadence (steps/min), single limb support (%), double limb support (%), and stride length (m) were averaged using both lower extremities' data. Root-mean-square (RMS) sway (m/s2), indicative of sway area posture stability, was also extrapolated. Cohen's D and power analysis were completed for effect size determination.

Eighteen patients with unilateral BKA with TMR were identified; 10 (55.6%) of the 18 patients had PAD. Patient characteristics, including age, body mass index, and Charlson Comorbidity Index, were comparable between groups (Table 1). Average gait speed (0.89 ± 0.08 vs. 0.58 ± 0.28, P = 0.01), single limb support (35.91 ± 1.50 vs. 31.68 ± 3.37, P = 0.01), double limb support (28.13 ± 2.99 vs. 36.71 ± 6.99, P = 0.01), and stride length (0.85 ± 0.08 vs. 0.71 ± 0.11, P = 0.01) were significantly different between non- PAD and PAD groups, respectively. There were no differences seen in elevation at midswing, step duration, cadence, or RMS sway (Table 2).

Patients with PAD undergoing BKA with TMR experience significantly impaired gait function compared to non-PAD patients. These findings highlight the need for tailored rehabilitation strategies to address this population's mobility challenges.